Is my computer the reason for a strange render screen?
It looks like you have 2 planes overlapping each other. Take a look at the outliner panel and check if there are duplicate plane objects in your scene. 

If you can't see the duplicate plane in the 3D viewport, but it shows up in render - It's very likely that you have either hidden (the eye icon in the outliner) or disabled (the monitor icon) it in your viewport. Click on the filter button and enable the toggles if you can't find them.